1. Field of the Invention
The present invention concerns hair clips such as are used by women's hairdressers, for example.
2. Description of the Prior Art
Prior art hair clips, such as those described for example in documents FR 770 805 A and FR 755 662 A and in patents U.S. Pat. No. 5,494,060 and U.S. Pat. No. 5,664,591, usually have a first jaw with a first series of generally parallel teeth, a second jaw with a second series of generally parallel teeth and hinge means connecting the first and second jaws and allowing them to pivot relative to each other about a hinge pin between an open configuration in which the first and the second series of teeth are moved apart and a closed configuration in which the first and second series of teeth are interleaved with each other.
In patents U.S. Pat. No. 5,494,060 A and U.S. Pat. No. 5,664,591 A the parallel teeth are curved in a circular arc shape and have a substantially constant and relatively small width along their entire-length.
In documents FR 770 805 A and FR 755 662 A the teeth have a triangular profile with a width that is maximal near their base and reduces progressively towards their free end.
As described in the above documents the hinge means connect the first and second jaws in their respective intermediate areas between two holding levers and the clamping areas provided with teeth and spring means urge the jaws to pivot relative to each other towards their closed configuration.
Other prior art hair clips or slides, as described for example in document FR 592 049 A, are hinged at one lateral end of the jaws and the teeth also have a triangular profile with a width which is maximal at the base of the teeth and decreases progressively towards their free end.
With hair clips like those of the prior art one useful function is to assure good retention in the hair and to hold as much hair as possible.
It is nevertheless found that retention in the hair is less than perfect, because locks of hair tend to slide progressively between the teeth and the hold loosens.
Document FR 1 049 705 A describes a clip with two hinged jaws for holding a looped lock of hair. The teeth of each jaw are connected together along their base by a median bar, the two median bars being adapted to grip the lock of hair and to hold it away from the scalp, allowing air to pass between the teeth on respective opposite sides of each median bar to dry the hair. The part of the teeth projecting beyond the corresponding median bar has a width that decreases towards the free end of the tooth. The teeth have a triangular profile. The open part inboard of the corresponding median bar does not exercise the function of a row of teeth because the bar prevents penetration into a mass of hair. In the closed configuration of the clip the projecting part of the teeth extends along a circular arc entirely in the direction of the opposite jaw.
The problem addressed by the present invention is that of improving the retention of the clip in the hair by preventing locks of hair slipping between the teeth of the clip, in particular slipping in the mean longitudinal direction of the teeth.
Another object of the invention is to improve the "hold", by which is meant to increase the amount of hair that a given size of clip is able to hold.